The objective of this project is to synthesize and purify 0.4 mole or more of the peptide hormone atrial natriuretic peptide (ANP). This large scale solid phase peptide synthesis would be the first attempt to mass synthesize a peptide greater than 10 amino acids. Specifically, this project is aimed at developing the large quantity of the solid support resin which is needed for teh Fmoc peptide synthesis; preparing and analyzing a large quantity of Fmoc- tyrosine (otBu; and derivatizing the resin with the carboyl terminal amino acid of ANP, tyrosine.